1. Field of the Invention
The present invention relates to a seat and track assembly particularly adapted for mounting a seat in an operation station, such as an observer's seat in an operating station for an aircraft refueling boom.
2. Brief Description of the Prior Art
Since the present invention is particularly adapted for use in an operating station for an aircraft refueling boom, the prior art will be discussed with regard to that particular application. The usual method of aerial transfer of fuel from a tanker aircraft to a receiver aircraft involves the use of a refueling boom which is pivotally mounted to the lower rear end of the tanker aircraft. At the outer end of the boom there is an aerodynamic control apparatus (i.e. a ruddevator assembly) which is controlled by an operator positioned in the aircraft at a location proximate the interior end of the boom. The operator manipulates the ruddevator through appropriate controls to "fly" the boom into position for proper rendezvous with the receiver aircraft, so that the boom outlet can be properly positioned in that receptacle of the receiving aircraft. During refueling, there will be some relative movement between the two aircraft, so the operator continues to "fly" the boom during the refueling operation so that the boom follows the receiving aircraft without transmitting excessive lateral loads to the boom.
In operating stations which are now commonly used for refueling operations, the operator generally lies on his stomach facing rearwardly toward the boom, with his chin supported on a "doughnut-like cushion". However, this position is somewhat awkward and conducive to operator fatigue. Also, when a second person is positioned in the refueling boom operating station (e.g. in the situation where there is an observer or an instructor), the operation becomes particularly cumbersome. The second person must assume a prone position to one side or the other of the operator, and to obtain a view of both lateral extremes of the operating area of the boom, it is necessary for the second person to somehow move his head over the prone body of the operator.
Accordingly, there have been proposals in the prior art to modify the operating station so that the operator is in a sitting position. One such proposal is described in a U.S. patent application, entitled "Operating Station for Aircraft Refueling Boom", the inventor being Thomas H. White, this application being filed at or about the same time as the present application and being assigned to the same assignee of the present application. In that proposal, the operator's seat is located within the lower rear portion of the aircraft fuselage, with the seat positioning the operator in a moderately reclining sitting position facing rearwardly to view the operating area of the refueling boom. Two rearwardly and outwardly diverging leg well structures provide recesses to accommodate the operator's legs, and the viewing window is positioned between the operator's legs at approximately the position of the operator's knees.
There are also provided one or two observer's seats which are movably mounted in the operator's station so that the observer can be positioned on either side of the operator or in line with the operator so that he is looking directly over the operator's head toward the refueling area. Thus the observor's seat should be movable in a generally U-shaped pattern extending transversely along the back side of the operator's seat and longitudinally along each side of the operator's seat. Since the tanker aircraft may under some circumstances be subjected to negative "G" loads, it is also necessary that the observer's seat be securely mounted to the aircraft's structure. Further, since the observer will most all of the time be looking in the same general direction toward the operating area of the refueling boom, it is desirable that the base of the observer's seat maintain the same orientation with respect to the aircraft in spite of being moved along different directions of travel around the operator's seat.
With regard to the prior art appearing in the U.S. patents, the following are noted:
U.S. Pat. No. 307,850, Edwards, shows a bookkeeper's chair or stool mounted by four rollers to a pair of parallel transversely extending rails.
U.S. Pat. No. 1,167,932, Robertson, also shows a bookkeeper's stool mounted for lateral movement. In this patent the stool is mounted by a pair of upper rollers and a single lower roller to a pair of rails spaced one above the other.
U.S. Pat. No. 1,430,465, Niemuth, shows a swivel chair having four base rollers mounted to a pair of parallel tracks extending across the front of a desk.
U.S. Pat. No. 3,305,264, Gunn, shows an adjustable aircraft seat mounted by rollers to a pair of parallel forwardly and rearwardly extending rails.
U.S. Pat. No. 3,993,280, Surbaugh, shows a drafting stool mounted by rollers to parallel laterally extending rails.